And - all done!

Hushmat on only the plastic black part, about a 30% improvement. The same for me as Dynamatting the entire trunk spare tire well thing.

I then bought this.


I put this product underneath the trunk cover, and stacked two layers over each other.

OMG - the result is crazy. I can floor the snot out of my car and I don't hear the exhaust.

A definite mod. Part of me wants to try not Hushmatting the plastic thing at all and seeing if the Dynamat Hoodliner is all that one needs, but I am not removing that damn thing again - my back kills as is.

Hope that helps

Only downside is...

Man now I feel my engine is too loud But no regrets. A definite must do.

 

I truly feel someone needs to try the roof. When it rains it sounds as if there is no insulation at all. Very loud. I feel this would help with overall road noise.

 

Couple of things

1) I have a panoramic roof, so that's really a no go. What you could do is use some noise isolating window film to help, but then you'd be losing the view.

Even if I had a metal roof I wouldn't dare do that out of condensation/rust concerns.

Quite honestly, I don't know if you're right or not. I have triple sealed some doors (car comes with double seals), and I don't think I've improved it in any meaning way. I put some of that dynaliner thing underneath the front steering wheel component (top of footwell), and not sure if that helped any.

I'm done adding stuff b/c the car is pretty quiet now. If I had money for a Rolls, I'd buy one, but this is good enough

 

I put this stuff on the inside of my fender liners when I had them out doing new shocks. It made a noticeable improvement in tire/road noise, which I have a lot of due to 18" AMG wheels and the miserable chip-seal pavement they use here in Texas.

Great thread, I think I have enough leftover material to cover that plastic trunk floor panel next. The sound of engine and exhaust are pretty muted already, but every bit of road roar I can get rid of will make the car that much more enjoyable on long trips.

 

Did you do all 4 wheels? And, did you happen to take any pics? Thanks

 

how do you guys have drone on a stock c300?

 

I'm referring to exhaust noise. I'm already on grand touring Michelins. It's really difficult to explain and hard to understand until you've done these various mods.

Here's a way to test it.

Let's say you're driving uphill, or when the car is under quite a bit of load (onramp on a highway), or you're flooring the snot out of it. As you're accelerating hard, stick your head such that it's between the two front seats and turn your ear. Focus on listening to the trunk area. You'll hear the exhaust tone, especially around 2500rpm to 4500rpm. It's pretty low in frequency.

That's what I've managed to get rid of. I never thought my engine was "loud" until I got rid of that noise in the trunk.

 

Good morning. I did all four corners ... in the front the fender liner is in two parts, so I did just the rear half closest to the passenger compartment. On smooth pavement the car is super quiet but unfortunately we have very little smooth pavement where I live.

And sorry, no pictures to share, never think of that until after everything's finished and put back together!

 

How big was the difference for you with regular not smooth pavement? My car is already dead quiet on smooth pavement due to my tire choices, although there is room for improvement on normal not so smooth pavement. Wondering if it was night and day for you?

Also which product did you use? Thanks

 

Resurrecting a very old thread.
My W210 on the highway is like driving a 747 - quiet, solid and extremely comfortable.
My W204 is the opposite of this. I was shocked in the NVH deterioration from the W202 to the W204.
I have gone the bituminous sound proofing route underneath the car, in the wheel wells and in the trunk space. I have installed Dynamat here there and every where. The results get somewhere near the W202 stock standard without additional sound proofing.
The W204 will never get near the W210 quietness and smoothness level whatever I do to it. It's just the way the contemporary marketing departments have had the cars designed for the current customers and government mandates which require lighter cars for less fuel consumption and emissions.

Having said all that. Hail on the roof of my old W202 or W124 would make a muffled thud thud thud sound. Hail on the roof of the W210 makes a tin can plink plink plink noise.

 

Holy sh** Long time lurker much? LOL

What year of the W204 did you drive? In 2013 MB introduced the Blue Efficiency line which removed a bunch of sound deadening. My 2012 model does not have that crap so I find the NVH to be pretty good. That said I haven't driven a W210 though.

 

Unfortunately I forgot to properly measure and did not cover the whole trunk well. I used Noico which is 8 lbs. Is that heavier than what you used?

If something is more expensive and lighter than that would be another reason to spend more.

 

Comparing 10 square feet it's 5.5 lbs lighter vs 8 lbs for Noico. Noico was only $20 vs for 62.98.

Noico isn't bad stuff but I'm wondering if I should start over.

 

Hello guys.

Since I have been working on insulation for a while I would like to share my experience.
My clk is a 2007 200K with 17'' sportpack with michelin ps4 tyres. Living in Turkey. Roads can be seriously terrible because of the texture. If you drive long distances it would be mixture of good quality to bad quality.
I have covered the trunk first with something like a stage 1 stuff with a second layer of sound insulator. Cannot compare the quality of the stuff that you mentioned but I can easily say the ones I use are not good as yours.
Trunk made a real difference for sure. Then doors with same stuff while I was replacing my speakers with the headset. I will definitely recommend this if you like a difference for the speakers.
Hood... I think this made no difference in my situation. In my opinion this would be the last location through a complete insulation.
Then rear wheel arches. I can easily say that this made a nice difference but in highway speeds with bad texture, does not make so much difference with high pitch noise.
As Glyn said previously, when you start this insulation thing you notice different noise from specific locations. In my opinion wheel arches and under seats with trunk would make the best noise insulation in our cars if you really want a good improvement.
Next thing the floors for sure. I will try to use much quality stuff as I can effort.Now when I listen to noise levels in back seats I can easily say that there is a noise coming from the floor like a tunnel noise but not annoying. Front wheel arches, floors and the firewall will be next focused areas.
One more thing... Used different set of tyres and I can easily say that michelin ps4 is the noisiest most exaggerated tyre in my opinion. Used goodyear excellence before this one, conti 3 which sucks generally but definitely quieter then ps4 and p zero of course. PS4 is like soft eraser that finishes so quickly. Performance wise whoever saying ps4 is great is probably believing in marketing gimmicks. Goodyear was as good as ps4 and I sometimes drive like and animal while cornering. Not saying I am proud of it but I do.
Replacing the rears with asymmetric 3 this week. Hope it is quieter than ps4.

 

You don't have to blanket everything and give yourself a weight penalty , just use a knuckle to tap out areas of resonance .

 

In addition to the sound deadening layers, has anyone added some other product? The layers reduced the sound like two bars but it is still somewhat noisy. Wondering if should stick another layer on top or if there is another product that can be used. Any suggestions please? Very much appreciated.

 

I observed that a lot of Mercedes cars have a noisy floor. In 211, 204 and 212 FL they have a lot of noise coming from the rear floor.
The noise you are hearing comming from behind, between the frojnt seats is actually the floor, not the windows!

In all of these models start by damping the floor. No need to add 3 layers, a good damping layer will do wonders. An of course only on the thin parts of the metal, no need to put foil over the strong parts as they don't vibrate and do not transmit the sound. Only high frequencies which are absorbed by the thick floor mat anyway.
There i no point in doing the doors or the trunk before doing the floor.

I done it, that is how i know.

Before starting make sure to get quiet tires. It is the cheapest and the simplest problem to solve.

For a 211 the priorities are:
- floor all of it, only the thin parts
- getting fabric rear arch covers from w211 wagon and cover their rear grill as sound propagates through there towards the trunk grill.
- covering interior rear wheel arches, again only the thin parts of the metal and get C class w203 rear arch cloth covers and over it put the original material
- you could add some cloth to the behind of the trunk linings to dampen the sound there. You could use materials from a scrap yard but i guess it is a hustle getting them clean.
- improvise with some carpeting for the front wheel arch covers, they remove a lot of the tire hissing noise that enters through the window.
- engine noise will be the dominant noise now, so you dampen and cover extra with 3 layers under the steering wheel down to the carpet. You could cut the factory material, put yours and then put back the original material. It is a lot of work, i know. However is necesarry, otherwise, without this intervention you will notice that the engine noise is a lot louder from the driver's seat than from the passengers seat.
From the passenger seat it will feel like the engine is on the left side of the car, from the driver seat the engine feels in front of you. A clear indication.
And the engine is not a low end, lion roar like noise, it is screaming with mid frequency and it is annoying as the rest of the car is a lot quiter.

- if this is till not enough go for the doors but very lightly. they are good as they are.
For the doors just put a few strips on the lower part of the door so it won t sound like bare metal. Then cover the big hole with some damping material so it will block the noise.
That would make the metal door a lot quieter than the window. Anything more is just waste of material and adds weight to the door.
Stop taking advice from pictures showing the door fully covered with material. That is plain stupid as the window is much noisier than the door, and the window sticks right into your ear.

Don't touch the ceiling. Waste of time, it is good as it is.
Don't do the spare tire compartment. the door above the spare tire does a good enough job.
Don't touch the trunk door, maybe put some textile material behind the lining, but improvement would be marginal at best.
on't touch the rear quarter panels.

As i rode and listen in a 212, the trunk is quite well insulated and same for the doors, but the floor is not. So start with the floor and then ride in the back and see if you can hear anything comming from the back.
Then you could go for spin and see that would be the next step.

The biggest mistake that most of us do, including myself is starting with the doors and the trunk because it is easy, however the floor is much louder as it is almost untreated. You cannot see any improvement in the mentioned cars: 211, 212, 204, 203 until you don't get the floor fixed.